Although the idea of the public interest features prominently in many accounts of deliberative democracy, the relationship between deliberative democracy and the public interest is rarely spelt out with any degree of precision. In this article, I identify and defend one particular way of framing this relationship. I begin by arguing that people can deliberate about the public interest only if the public interest is, in principle, identifiable independently of their deliberations. Of course, some pluralists claim that the public interest is an implausible idea, which casts doubt on the idea that there might be something for people to deliberate about. Yet while, following Brian Barry, we can get around this problem by defining the public interest as an interest in which everyone shares qua member of the public, what still needs to be explained is why people should be prepared to privilege this particular capacity. I argue that the account of political equality with which deliberative democracy is bound up offers a compelling explanation of this sort, even if it also gives rise to some difficult questions of feasibility. I conclude by considering the charge that any political scheme that framed the relationship between deliberative democracy and the public interest in this way would be undesirable